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Algebra Difficulty 1.7 Junior Find the answer

If 4n=6424^{n}=64^{2}, what is the value of nn?

A number or a short expression. Spacing and $ signs are ignored.

Solution

We note that 64=4×4×464=4 \times 4 \times 4. Thus, 642=64×64=4×4×4×4×4×464^{2}=64 \times 64=4 \times 4 \times 4 \times 4 \times 4 \times 4. Since 4n=6424^{n}=64^{2}, then 4n=4×4×4×4×4×44^{n}=4 \times 4 \times 4 \times 4 \times 4 \times 4 and so n=6n=6.

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